Over the years Star Trek has had its share of creepy moments, and we’re not just talking about that guy in the skant who roams the Enterprise-D corridors in “Encounter at Farpoint.” Long before the man dress was unveiled The Original Series set the tone for spooks in space with the episode “Catspaw.” While this was the first and only real Star Trek Halloween special (it aired October 27, 1967) there have been many more thrills and chills worthy of All Hallows Eve. Here’s a partial list to help you line up a spine-tingling night of Trek.

“Catspaw” (TOS)

“Crewman Jackson is dead.” What better way to start an episode that features a haunted castle, witches, black cats, and enough smoke to rival an Adam Lambert concert. In this story the crew find themselves at the mercy of a witch and wizard. Kirk, Spock, and McCoy end up in a dungeon filled with skeletons, the Enterprise is transformed into a pendant held to flame, and Chekov sports particularly frightening hair. “Catspaw” remains essential Halloween viewing for any Star Trek fan. The fact that Fraggles turn out to be behind it all makes this story even spookier.

“The Enemy Within” (TOS)

It’s a futuristic twist on the classic tale of Dr. Jekyll and Mr. Hyde in “The Enemy Within.” When a transporter malfunction splits Captain Kirk into good and evil halves, a psychological thriller unfolds. The crew must find a way to stop the increasingly erratic evil half of Kirk in time to save the landing party that is freezing to death on the planet below, as well as the ship itself. Not cut from the same Halloween cloth as “Catspaw,” but still an eerie look into the internal struggle of the mind.

“Wolf In the Fold” (TOS)

Foggy alleys, dead dancers, and bloody knives. “Wolf In the Fold” is another space-age twist on one of our best-known tales of horror that attempts to explain the mystery of Jack the Ripper, the serial killer who terrorized London in 1888. Placed under arrest and accused of murdering several women while on shore leave, Scotty finds himself intertwined with Jack the Ripper himself and in this story written by Psycho author Robert Bloch.

“Night Terrors” (TNG)

Corpses seem to come to life and Worf tries to commit suicide in this psychological thriller about what would happen if we were unable to dream. The Enterprise finds the crew of the USS Brittain dead in what appears to have been a case mass homicide. Soon dream deprivation and paranoia begin to incapacitate the Enterprise crew, threatening them with the same loss of control that led to the demise of the other Brittain’s crew. It is up to Troi’s unique empatic powers to communicate with others suffering the same fate and free the ship.

“Schisms” (TNG)

One of the creepiest episodes of Star Trek: The Next Generation, “Schisms” is the story of abduction and medical experimentation. Enterprise crew members report that they wake up exhausted and show signs of traumatic memories. Possibly as close to horror as you’ll get in a Star Trek episode, “Schisms”—with its terrifying subspace aliens—brings forced, sinister experiments and a sense of helplessness that turns the table on a crew that is normally in control. Unusually dark for TNG.

“Frame of Mind” (TNG)

You’ve always thought Riker was a little bit psycho right? “Frame of Mind” is another of Brannon Braga’s twisted psychological takes on Star Trek. An angry and paranoid William Riker finds himself trapped in a mental asylum—part of a scene from a play in which he is performing that suddenly appears to have become real. As the story goes on it becomes increasingly difficult to separate reality from dream and hallucination, both for Riker and for the viewer.

“Sub Rosa” (TNG)

Beverly Crusher finds herself in a ghost story that delves into her family history. A low-key tale more in the vain of a haunted classic, “Sub Rosa” begins with the funeral of Beverly’s grandmother and takes creepy twists and turns to reveal a common unworldly link that connects many generations of women in her family. Under the influence of an ancient ghost who claims to have been part of the Howard family for hundreds of years, Crusher almost resigns from Starfleet.

“Empok Nor” (DS9)

Deep Space Nine’s haunted house episode, “Empok Nor,” sends a ragtag crew led by O’Brien to an abandoned Cardassian space station to salavage parts needed in the repair of Deep Space 9. The crew find themselves under attack by drug-influenced occupants of the station with no way to escape or call for help. Then, in a fight for survival, they turn upon each other when Garak falls under the spell of the drug.

“The Thaw” (VOY)

When your only reality is an illusion, then illusion is reality. A truly twisted episode, “The Thaw” places the Voyager crew face-to-face with the personification of fear. It’s a case in which people are literally scared to death. Far from an element of entertainment, Michael McKean’s clown in one of the most psychotic characters you’ll find in Star Trek. “The Thaw” is an excellent story about how extreme fear can take over and paralyze a person.

“Darkling” (VOY)

It’s another Star Trek take on Dr. Jekyll and Mr. Hyde when the Doctor’s personality turns toward evil in “Darkling.” Attempting to enhance his program by incorporating various historical personalities, the Doctor’s subroutines become unstable leading him to harm his patients and use his medical knowledge for sadistic purposes, even going so far as to intentionally paralyze B’Elanna from the waste down when she refuses to cooperate with him.

“The Haunting of Deck Twelve” (VOY)

There are shades of kids on a camping trip and ghost stories by the fire in this spooky episode of Voyager. As the ship is forced to power down, Neelix meets the Borg children with a plasma lantern. He attempts to keep them occupied by sitting around the lantern and telling stories of the ghost that is said to live on deck 12. Grab your stick and marshmallows and prepare for a fright.

“The Haunting of Deck Twelve” (VOY)

On one of their first encounters will alien life, the crew of the Enterprise NX-01 boards an abandoned ship and uncovers a large number of corpses. It’s a truly creepy moment when they discover a room of dead bodies hanging updside down, having been washed out with some sort of fluid. “Fight or Flight” is a frightening introduction to the larger universe for the crew of the first Warp 5 ship and an example of how humans may react to the unknown.

“Dead Stop” (ENT)

Crippled and in need of repair the Enterprise NX-01 encounters an unusual alien space station. The station is able to provide services for a very modest fee. Another episode with a haunted house theme, the automated space station is filled with mysteries and its extremely sterile nature alone is disconcerting. Add to this that fact that its offer of repairs seem too good to be true, Mayweather is seemingly killed, and the station later threatens the very safety of the ship itself, and you have one oddly creepy stopover for the NX-01.

“Impulse” (ENT)

Zombies! Zombies! And not just regular zombies but Vulcan zombies. That’s what you’ll get in the Enterprise episode “Impulse,” in which Archer and his crew find a Vulcan ship adrift, its crew mindless and out to get anyone who comes aboard. And T’Pol may be the most vulnerable of all.

So there you have it—a handful of frightening moments from all five live-action Star Trek series. There are certainly others but this collection is a great starting point for a spooky journey through Federation space and beyond.